Thanks Raul,
I added your ‘tail' implementation to the code and it works without issue. The
KJV text is listed in reverse line order in the output file.
benchmarks ''
sumloop: 0.227858 8.39149e6
sumj: 0.000171 1.04986e6
ack: 2e_6 721472
array1: 5.6e_5 1.05107e6
array1t: 4.8e_5 1.05107e6
string1: 0.003969 2.88634e6
cat: 0.01474 2.51685e7
wc: 0.295076 1.58152e8
tail: 0.065197 3.77133e7
sum1: 0.12709 4.04989e7
sum1j: 0.000547 1.18086e6
I have placed the code on GitHub:
https://github.com/tmcguirefl/JBenchmarks
The scheme folks have put together a large set of benchmarks at:
https://www.ccs.neu.edu/home/will/Twobit/benchmarksAboutR6.html
When time permits I will go through them and implement the ones that would be J
appropriate (some do symbolic differentiation which would be nontrivial for me
to code into J).
Tom McGuire
> On May 18, 2021, at 9:04 PM, Raul Miller <[email protected]> wrote:
>
> Here's the tail benchmark written in J:
>
> tail=: 4 : 0
> (;|.<;.2 freads x) fwrites y
> )
>
> This is based on my reading of the C implementation of the tail
> benchmark vs the cat benchmark, and on the cat benchmark in this J
> implementation, except that I have failed to reproduce a bug in the C
> implementation which shows up when the file contains very long lines
> and instead I have assumed that the file ends in a newline (which is a
> valid assumption for the gutenberg kjv bible).
>
> Let me know if you think I have made a mistake here.
>
> Thanks,
>
> --
> Raul
>
> On Tue, May 18, 2021 at 7:02 PM Thomas McGuire <[email protected]
> <mailto:[email protected]>> wrote:
>>
>> I was going over Devon McCormick's notes from the latest NYCJUG meeting.
>> There was a discussion about Benchmarks with an example of the Kernighan/Van
>> Wyk benchmarks in LISP/Scheme. Devon had made the comment that for most
>> things people use J for that correctness overshadowed performance.
>>
>> The K/VW benchmarks were originally made for C and seem to test looping
>> controls and memory allocation which at a time of low memory minicomputers
>> and PCs, coupled with multiple available C compilers, made the benchmarks a
>> nice way of comparing compiler implementations as well as new processor
>> speed.
>>
>> However it seemed like a simple project to exercise my J programming skills
>> with so I have attached the program to this email.
>>
>> Note: you will need to download the King James Version of the Bible from
>> project Guttenburg (not included with the attachment) to run the full
>> benchmarks. I also created my own file of floating point numbers to sum
>> (routine to create a file of random floats is included). I have added some
>> routines to accomplish similar functionality in the way I would do it in J
>> (at least for my mere mortal understanding of J).
>>
>> Running on my mac book pro (2016 with 2.9 Ghz Quad core I7) the results are:
>>
>> benchmarks ''
>> sumloop: 0.214383 8.39149e6
>> sumj: 0.000162 1.04986e6
>> ack: 4e_6 721472
>> array1: 0.000578 1.05107e6
>> array1t: 2.5e_5 1.05107e6
>> string1: 0.003237 2.88634e6
>> cat: 0.014234 2.51685e7
>> wc: 0.302383 1.58152e8
>> sum1: 0.124006 4.04989e7
>> sum1j: 0.000956 1.18086e6
>>
>> thought I would share
>>
>> Tom McGuire
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